Energy Micro adds Cortex-M4 based MCUs

LONDON – Energy Micro AS has introduced a family of 32-bit microcontrollers at the top end of its range based on the ARM Cortex-M4 with floating-point unti and single-instruction, multiple data (SIMD) capability.

The chip family – which comes in 60 variants of memory, peripheral and packages options – is manufactured for Energy Micro by foundry Taiwan Semiconductor Manufacturing Co. Ltd. and uses an extreme low leakage option (eLL) to minimize power consumption for battery-powered applications. The eLL option was introduced by TSMC at the 0.18-micron node.

Alf-Egil Bogen, chief marketing officer of Energy Micro (Oslo, Norway), said the "Wonder Gecko" was looking to provide good performance at megahertz clock frequencies but with excellent energy efficiency. "The point is we want to get processing done quickly. The key is to get the core back to sleep as much as possible," he said. Typical applications could be local processing, including filtering and running FFTs, of sensor data in battery-operated systems, he said.

The features of Energy Micro's established Cortex-M3 based devices, including low-energy sensing and the "reflex" system that allows certain peripherals to communicate with each other without waking the core, have been carried forward, said Alf-Egil.

"Embedded designers have asked for lower power-down current at higher temperatures. To support this we have been working with TSMC to utilize new technology that cuts the power consumption in half at 85 degrees C," said Energy Micro’s chief technology officer, Oyvind Janbu, in a statement.

The Wonder Gecko family consists of 60 scalable memory and package configurations with up to 256-Kbyte of flash memory and 32-kbytes of RAM and QFN64 to BGA120 options.

Design tools for planning, coding and design verification are supported by Energy Micro’s free Simplicity Studio suite. It includes the CMSIS-DSP library with over 60 functions in fixed-point and single precision floating-point 32-bit implementation, and documentation for DSP algorithms such as complex FFT, FIR filters, matrix and vector operations and statistical analysis. The software includes applications for power-oriented debug and for resolving pin-out conflicts, said Bogen.

The EFM32 Wonder Gecko microcontrollers cost from $2.64 in 100,000 unit quantities. The accompanying starter kit with built in J-Link debugger, the EFM32WG-STK3800, costs $79, the company said.